An electric compressor used in a vehicle air conditioner includes a circuit assembly that bears circuits for controlling the driving of a motor. The circuit assembly includes a circuit board to which various circuit components are connected. The circuit board is affected by engine vibrations, road surface vibrations, and the like, and is therefore subjected to a harsh vibration environment.
When vibrations from the periphery of the circuit board cause the circuit board to vibrate, a heavy load is placed on large-size and high-mass electronic components affixed to the circuit board, such as a transformer. Transformers are affixed by soldering the distal ends of lead frames that constitute the transformer to the circuit board.
However, in harsh vibration environments, there is a risk that the lead frames will be damaged, cracks will appear in the soldered portion, or the like, causing the transformer to separate from the circuit board.
Accordingly, a technique that reduces vibrations transmitted to a circuit board by filling a space that contains the circuit board with a resin-based gel material has been proposed (Patent Documents 1 and 2).